Missoula Scientists Study Wind Flow and the Affects on Firelines

By MARK VOSBURGH

You may have seen these amazing depictions of winds across the country developed by scientists at MIT and UC Berkley.

National Wind Map

National Wind Map

Closer to home, researchers at the UM Flight Lab  and the Missoula Fire Sciences Lab are working to understand the intricacies of wind flows at smaller scales.

Dr Bret Tobalski and his team at the flight lab work to shed light on one of nature’s most profound phenomena: Flight.  Using a technique that combines lasers, high speed cameras and computers, the Flight Lab has captured amazing images depicting air flow and aerodynamic wakes left behind bird wings during flight.

Zebra Finch in Flight

Zebra Finch in Flight

Wake left behind Zebra Finch in Flight

Wake left behind a Zebra Finch in Flight

 

Air Flow Around Bird in Flight Capture with Lasers

Air Flow Around Bird in Flight Captured with Lasers

Air flow around a bird at UM Flight Lab

Air Flow Around a Bird at the UM Flight Lab

By analyzing these images researchers are able to better answer questions such as: How do birds fly and how might we incorporate these insights in to human flight?

On every wildfire fire incident, fire bosses and crews have a critical need to predict what winds be doing on the fire line.  Traditional weather forecasts predicts wind on a grid size of 12 kilometers or about 7.5 miles. These forecasts do not predict the flow of wind around the complex terrain where fires often burn.

Dr Bret Butler and Jason Forthover, mechanical engineers at the Fire Lab are developing a tool to help the wildfire community better predict wind flows in these situations.  Their software “Wind Ninja”  takes large scale weather forecasts, combines them with terrain, vegetation the effect of solar heating to predict wind speeds and directions on a scale of 100 – 200 meters.

National weather service recently predicted the wind speed in Missoula to be around 15 mph from the west.  Wind Ninja took this prediction, broke it down smaller grid and calculated wind speeds of over 30 mph on top of Mount Jumbo and under 7 mph in the lower Rattlesnake.   This type of information can be invaluable to wild land firefighters.

Missoula Area Windflow Predicted By Wind Ninja Software

Missoula Area Wind Flow Predicted By Wind Ninja Software

Wind flow around Montana's Highest Point

Wind Flow Around Montana’s Highest Point

Windflow around Wildhorse Island Flathead Lake

Wind Flow Around Wildhorse Island Flathead Lake

Forthover says recent testing shows the model to be most accurate on ridge tops and the upwind side of mountains.  The team is working on improving predictions on the leeward side of obstructions.

If you are curious about wind predictions in your favorite area, try out the latest version of Wind Ninja.  The program is designed to work on laptops and personal computers along with Google Earth and includes a help manual and tutorials to get you started.

And be sure to check out the Flight Lab Facebook Page.

Special thanks to Jason Forthover, Kyle Shannon and Natalie Wagenbrenner at the Missoula Fire Lab and Brett Klaassen Van Oorschot at the UM flight lab for help with this article.

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Mark Vosburgh is a fourth-generation Montanan from Boulder and a 26-year resident of Missoula. He’s worked as a chemical engineer, backcountry ski guide, and wildfire scientist. He plays in several local bluegrass bands and enjoys the usual assortment of Missoula’s great outdoor opportunities. Check out the Ski It Missoula archives for more ski posts by Mark and more local skiers.